Charles manlius hoffman



(No Model.)

O. M. HOFFMAN.

POLE OR THILL COUPLING.

Patented De0.7, 1897.

UNiTED STATES PATENT OFFICE.

CHARLES MANLIUS HOFFMAN, OF LEBANON, NEW HAMPSHIRE, ASSIGNOR OF ONE-HALF TO ISAAC N. PERLEY.

POLE OR THILL COUPLING.

SPECIFICATION forming part of Letters Patent No. 595,019, dated December '7, 1897.

Application filed August 26, 18 97.

To aZZ whom it may concern:

Be it known that I, CHARLES MANLIUS HOFFMAN, a citizen of the United States, residing at Lebanon, in the county of Grafton and State of New Hampshire, have invented certain new and useful Improvements in Interchangeable Pole or Thill Couplings; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertain-s to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

It is often desirable to exchange the shafts of a vehicle for a pole, and vice versa; and the object of my invention is to do away with the ordinary bolt and nut and to provide a simple and secure coupling which will permit the rapid exchange above mentioned.

The nature of my invention will be described below and pointed out in the claims.

In the drawings, Figure 1 is a side view, partly broken. Fig. 2 is a broken plan view. Fig. 3 is a detail of the draw-bolt. Fig. 4 is a detail of the locking-plate, partly broken.

Like letters refer to like parts.

A is a clip, and B are the clip-jaws.

C is a thill-iron having a draw-head D with a circular eye.

E is the draw-bolt. At one end it has an enlarged circular head f with a circular groove a. The other end has transverse square grooves 17 out in quite deeply, also two slight seats 0, and the purpose of these grooves and seats will appear below.

H is a locking-plate. This has a keyholeshaped slot (2. The outer face of said plate is irregular, but mostly wedge-shaped, so that when the plate is driven downward it looks tighter and tighter in grooves b in the drawbolt but when driven upward quickly loosens and releases said bolt when the end opposite the head registers with the circular portion of slot cl.

L is a latch pivoted to locking-plate H. On its rim it has a thumb-piece and on its rear Serial No. 649,620. (No model.)

face a knob 7', which snaps into the slot of plate H when the latch is closed and prevents the latter from getting loose. The latch when locked also engages with one of the seats a in the draw-bolt, which gives additional stability to the latch, the purpose of which is to prevent the plate H from working 5 5 plate H by drilling a hole in its top and inserting a cord.

The operation of the device is as follows: To remove shafts, pull back the latch, drive the plate H up until circular portion of slot cl registers with the end of the bolt F, opposite the head f, and then remove plate H and bolt E, when the drawhead can be removed. T0 attach a pole, insert it in proper place, pass bolt E through until the head f rests tightly against the clip-j aw, insert plate H, and drive 7 5 it down tight, or until the latch will look hard under the bolt.

Having fully described my invention, what I claim, and desire to secure by Letters Patent, is a 1. The combination with the clip-jaws and draw-head, of a draw-bolt with transverse grooves at one end, a slotted, wedgeshaped loeking-plate engaging with said grooves, and

a latch closing over said plate and under the end of said bolt projecting outside of the plate, as set forth.

2. The combination with the clip-jaws and draw-head, of a draw-bolt with transverse grooves at one end, a locking-plate wedgeoo shaped or partially inclined on its outer face and having a keyhole-shaped slot engaging said grooves in the draw-bolt, and a latch closing over said plate and under the end of said bolt projecting beyond the plate, as set forth.

3. The combination with the clip-jaws and keyhole-shaped slot when the latch is closed, draw-head, of a draw-bolt having at one end as set forth. 10 an enlarged, grooved head and at the other In testimony whereof I affix my signature end transverse gro0ves,a1ocking-p1ate Wedgein presence of two Witnesses.

5 shaped on its outer face and having a key- CHARLES MANLIUS HOFFMAN.

hole-shaped slot engaging with said grooves Witnesses: in the draw-bolt, and a latch provided on its 7 J. L. SPRING,

rear face with a knob adapted to look into said H. F. KNAPP. 

